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레독스 흐름 전지의 전극으로 사용하기 위해 탄소펠트를 열처리와 산처리 방법으로 산화 개질하였다. 열중량 분석결과 열처리 또는 산처리에 의하여 탄소펠트의 섬유 표면에 고분자 물질이 제거되고 산소 관능기가 도입된 것을 확인할 수 있었으며 습식 방법인 산처리 방법보다 건식방법인 열처리 방법이 기계적 안정성을 유지하는데 효과적인 처리 방법으로 나타났다. XPS, 원소분석을 통하여 500 $^{\circ}C$ 에서 4시간 열처리한 탄소펠트의 표면에 산소 관능기가 부가된 것을 확인하였으며 질소흡착실험에서 거의 없던 표면적이 96 $m^2/g$ 로 증가한 것을 알 수 있었다. CV실험 및 분극 실험을 수행한 결과 500 $^{\circ}C$ 열처리 전극의 활성화 저항이 가장 낮게 나타났다. 산처리한 탄소펠트와 400 $^{\circ}C$ , 500 $^{\circ}C$ 에서 열처리한 탄소펠트를 이용하여 바나듐 레독스 흐름 전지를 구성하고 충/방전 실험을 실시한 결과 충/방전 전압효율이 산처리 전극의 경우 86.6%, 400 $^{\circ}C$ 열처리 전극의 경우 89.6%, 500 $^{\circ}C$ 열처리 전극의 경우 90.6%로 500 $^{\circ}C$ 열처리 전극이 가장 우수하였다. 【Carbon felt surface was modified by heat or acid treatment in order to use for the electrode of a redox-flow battery. Polymers on the surface of carbon felt was removed and oxygen-containing functional group was attached after the thermal treatment of carbon felt. Thermal treatment was better for the stability of the carbon structure than the acid treatment. Oxygen-containing functional group on the thermally treated carbon felt at 500 $^{\circ}C$ was confirmed by XPS and elementary analysis. BET surface area was increased from nearly zero to 96 $m^2/g$ . Thermally treated carbon felt at 500 $^{\circ}C$ showed lower activation polarization than the thermally treated carbon felt at 400 $^{\circ}C$ and the acid-treated carbon felt in the cyclicvoltammetry and polarization experiments. The thermally treated carbon felts at 400 $^{\circ}C$ and 500 $^{\circ}C$ and the acid-treated carbon felt was applied for the electrode to prepare vanadium redox flow battery. Voltage efficiencies of charge/discharge were 86.6%, 89.6%, and 96.9% for the thermally treated carbon felts at 400 $^{\circ}C$ and 500 $^{\circ}C$ and the acid-treated carbon felt, respectively.】

In order to develop a novel polymer electrolyte membrane for direct methanol fuel cell (DMFC), styrene monomer was graft-polymerized into poly(tetrafluoroethylene perfluoropropyl vinyl ether) (PFA) film followed by a sulfonation reaction. The graft polymerization was prepared by the -ray radiation-grafting method. Subsequently, sulfonation of the radiation-grafted film was carried out in a chlorosulfonic acid/1,2-dichloroethane (2 v/v%) solution. The chemical, physical, electrochemical and morphological properties of the radiation-grafted membranes (PFA-g-PSSA) were characterized by fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM). The water uptake, ionic conductivity, and methanol permeability of the PFA-g-PSSA membrane were also measured. The cell performances of MEA prepared with the PFA-g-PSSA membranes were evaluated and the cell resistances were measured by an impedance analyzer. The MEA using PFA-g-PSSA membranes showed superior performance for DMFCs in comparison with the commercial Nafion 112 membrane.

A Pt-layer was deposited on the anode side of a Nafion membrane via a sputtering method in order to reduce methanol crossover in a direct methanol fuel cell (DMFC). The methanol permeation and the proton conductivity through the modified membranes were investigated. The performances of the direct methanol fuel cell were also tested using single cells with a Nafion membrane and the modified membranes. The Pt-layers on the membrane blocked both methanol crossover and proton transport through the membranes. Methanol permeability and proton conductivity decreased with an increase of the platinum layer thickness. At methanol concentration of 2 M, the DMFC employing the modified membrane with a platinum layer of 66 nm-thickness showed similar performance to that of a DMFC with a bare Nafion membrane in spite of the lower proton conductivity of the former. The maximum power density of the cell using the modified membrane with a platinum layer of 66 nm-thickness increased slightly while that of the cell with the bare membrane decreased abruptly when a methanol solution of 6M was supplied.

The composite membrane for direct methanol fuel cell (DMFC) was developed using powder and perfluorosulfonylfluroride copolymer (Nafion) resin. The perfluorosulfonylfluroride copolymer (Nafion) resin was mixed with powder and it was made to sheet form by hot pressing. The electrodes were prepared with 60 wt% PtRu/C and 60wt% Pt/C catalysts for anode and cathode, respectively. The morphology and the chemical composition of the composite membrane have been investigated by using SEM and EDXA, respectively. The composite membrane and were analyzed by using FT-IR and XRD. The methanol permeability of the composite membranes was also measured by gas chromatography (GC). The performance of the MEA containing the composite membrane (2wt% ) was higher than that of normal pure Nafion membrane at high operating temperature (e.g. ), due to the homogenous distribution of , which decreased the methanol permeability through the membrane and enhanced the water contents in the composite membrane.

Direct borohydrides fuel cell (DBFC) was emerged to complement the problem of DMFC`s low performance and methanol crossover to the cathode and to apply the fuel cell to portable and mobile devices. In this study, the characteristics of novel catalysts was tested to establish the electrode preparation process of DBFC. Pt black and carbon supported-Pt by paste method were used as the cathode catalysts. Pt black, carbon supported-Au and alloy were used as the anode catalysts. The characteristics of the electrodes were analyzed by XRD, SEM, EDS. The performance test of single cell using the electrodes were carried out in order to evaluate the electrode performance. In the result, the maximum power output was obtained as 366 mW/mg when using Pt/C as anode and cathode catalysts

For the development of low temperature anode-supported planar solid oxide fuel cell, the planar anode supports with the thickness of 0.8 to 1 mm and the area of 25, 100 and were fabricated by the tape casting method. The strength, porosity, gas permeability and electrical conductivity of the planar anode support were measured. The porosity of anode supports sintered at and then reduced in atmosphere was increased from . The electrical conductivity of the anode support was and its gas permeability was 6l/min at 1 atm in air atmosphere. The electrolyte layer and cathode layer were fabricated by slurry dip coating method and then had examined the thickness of and the gas permeability of 2.5 ml/min at 3 atm in air atmosphere. As preliminary experiment, cathode multi-layered structure consists of LSM-YSZ/LSM/LSCF. At single cell test using the electrolyte layer with thickness of 20 to , we achieved and 0.6V at

The performance of the Direct Methanol Fuel Cell (DMFC) using multi-layer electrode, which prepared by various anode catalysts and Nafion membranes, was studied for reducing the amount of the metal catalyst loaded in the MEA system. The amount of the catalyst used in this experiment was in cathode and in anode, respectively. The best performance was to be of MEA3 at and 2 bar in this experiment. However, the overall performance of the DMFC was maintained almost the same compared to the general commercial catalyst systems.